<!DOCTYPE html>
<html lang="zh_CN">
<head>
    <meta charset="UTF-8">
    <title>ATM取款机</title>
</head>
<body>
<script>
let money =100
    while (true){
        let re = +prompt(`
           请选择操作：
           1.存款
           2.取款
           3.查看余额
           4.退出
              `)
  //选择4 跳出循环
  if(re===4){
      break
  }switch (re){
            case 1:
                let cun = +prompt('请输入存钱金额')
                money= money + cun
                break
            case 2:
                let qu = +prompt('请输入取款金额')
                money= money - qu
                break
            case 3:
                alert(`银行卡余额为${money}`)
                break
        }

    }
</script>
</body>
</html>
